Grab bucket



June 5, 1956 G. F. THOMPSON 2,748,510

GRAB BUCKET Filed July 5, 1952 2 Sheets-Sheet 1 IN V EN TOR. 650565 E 7/oMPso/v BY l l June 5, 1956 Filed July 3. 1952 G. F. THOMPSON GRAB BUCKET 2 Sheets-Sheet 2 I N VEN TOR.

GE @6E/7 JOMPSO/v United States Patent O GRAB BUCKET George F. Thompson, Cleveland Heights, Ohio, assguor to The Wellman Engineering Company, Cleveland, Ohio, a corporation of Ohio Application July 3, 1952, Serial No. 296,993

Claims. (Cl. 37-186) This invention relates to grab buckets and, more particularly, to large capacity grab buckets of the clam-shell type.

' An object of this invention is to provide an improved relatively light weight, reinforced grab bucket capable of handling large loads in which the reinforcing members are so constructed and/ or connected to the corner members or bars of the bucket that there can be limited relative movement therebetween so that breakage of the reinforcing or corner members will be eliminated while preserving the desired strength and rigidity for preventing misalignment of the jaws or scoops of the bucket.

Another object of the invention is to provide an improved grab bucket capable of handling large loads wherein the individual corner members or bars of each pair thereof have reinforcing members extending therebetween and pivotally connected thereto in a manner permitting llimited relative movement between the reinforcing members and the corner members.

A further object of the invention is to provide an improved grab bucket of the clam-shell type capable of handling large loads and wherein the corner members or bars of each half or section of the bucket have a rigid substantially horizontal bar extending therebetween and pivotally connected thereto in a manner permitting limited relative movement of the members about axes which extend at right angles relative to the horizontal bar.

v An additional object of the invention is to provide an improved bucket of the clam-shell type capable of handling large loads which bucket has a rigid reinforcing framework extending between the corner members or bars of each half or section of the bucket and pivotally connected to the corner members for limited relative move- 'ment between the framework and members about axes which lie in vertically extending planes.

Another object of the invention is to provide an improved grab bucket of the clam-shell type capable of handling large loads and wherein the corner members or barsof each half or section of the bucket are interconnectedvby diagonally extending tension members in a manner providing a relatively light weight construction of requisite rigidity while permitting limited relative movement between the members thereby preventing breakage of the `connected parts.

Further objects and advantages of the invention will be apparent to those skilled in the art to which the invention pertains from the following description of the present preferred embodiment and a modification thereof, described withreference to the accompanying drawings in which: A Fig. llis a side elevational View of the presently preferred embodiment of a grab bucket constructed in accordance with this invention;

Fig. 2 is an end elevational view of the bucket shown in Fig. 1;

Fig. 3 is an enlarged fragmentary view of a portion of one of the corner members of the bucket substantially in 4the locality indicated by the broken lines 3--3 of Fig. l,

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illustrating the manner in which the reinforcing members are connected to the corner members or bars;

Fig. 4 is a side view of the structure shown in Fig. 3 with portions broken away to further illustrate the manner in which the reinforcing members are connected to the corner members in accordance with this invention;

Fig. 5 is a view similar to Fig. l showing in side elevation a modified form of grab bucket embodying the invention;

Fig. 6 is an end elevational view of the bucket shown in Fig. 5;

Fig. 7 is a View similar to Fig. 3 showing to an enlarged scale the portion of the bucket between the broken lines 7-7 of Fig. 5; and

Fig. 8 is a side elevational View of the portion of the structure shown in Fig. 7 but with certain parts thereof broken away to further illustrate the invention.

The grab bucket illustrated in Fig. 1 is of the clamshell type and is designed and adapted to handle relatively large loads, i. e., in the order of from five to fteen tons. The bucket comprises the usual head block 10 which is suspended by means of a holding cable 11 suitably connected to the head block and reeled in or played out by means, not shown, to correspondingly raise and lower the bucket. The head block 10 supports shafts or rods 12 and 13 extending horizontally along either side thereof on which are respectively pivoted spaced pairs of corner members or bars, such as 14, 15 and 16, the fourth corner member which is paired with the member 16 being obscured from view in the drawings. The pairs of corner members or bars at opposite sides of the head blocks are adapted to have limited swinging movement relative to each other about their respective shafts 12 and 13 and are vprovided with horizontally extending portions, such as 17 and 18, having interengaging teeth 19, as is well known in the art. j Y

The lower ends of the two corner members or bars 14 and 15 have a jaw or scoop 20 sometimes referred to as a half bucket pivotally connected thereto adjacent the rear portion thereof as by means of pivot pins 21 and 22. A complementary jaw or scoop 23 is similarly pivoted to the lower ends of the other pair of corner members or bars, the two jaws or scoops 20 and 23 forming the clam-shell bucket portion of the apparatus. The jaws or scoops 20 and 23 are each provided, adjacent either end thereof, with upwardly extending hinge plates, such as 24 and 25, which are pivoted to a lower sheave block 26 and have interengaging gear shaped teeth 27 and 28 for controlling the relative movement of the jaws or scoops and for facilitating aligning thereof in closed position. The lower sheave block 26 is provided with pulleys 29 which, together with the pulleys 30 in the head block 10, have the closing cable 31 reaved thereabout.

In operating buckets of this character the elevation of the bucket is controlled by suitably shortening or length- 'ening the holding line or cable 11, the jaws being moved to open position by lengthening the closing line or cable 31 so that the lower sheave block 26 may move downwardly relative to the head block 10 thereby causing the jaws or scoops 20, 23 to pivot about their connections with the sheave block 26 and about their connections with the corner members or bars. The corner members or bars may also partake of a limited pivotal movement about the shafts or pivots 12 and 13. Closing of the jaws or scoops 20 and 234 is accomplished by shortening the closing line or cable 31 thus elevating the sheave block 26 relative to the head block 10 so that the parts are restored to the position shown in Fig. 1, whereupon the material enclosed by the jaws or scoops may be moved by manipula- When a bucket of the nature just described is c011- structed for handling loads of large capacity such as, for example, coal or the like in quantities in the order of from five to fifteen tons, the corner members or bars should be laterally reinforced for the sake of greater strength and to insure proper alignment o f the jaws or scoops 20 and 23. However, in operation of such large capacity buckets the stresses are such, especially because of the tendency for the corner members to move relative to each other, that there is danger of breakage of welded or other rigid connections of the reinforcing members to the corner bars or members and, if the connections are made suciently strong, the weaker of the various reinforcing members or corner members may be broken. Moreover, increasing the Size of the parts suieentlv to eliminate such breakage increases the weight of the bucket. i'

In accordance with this invention grab buckets of the Clam-shell type., and which are adapted. for handling loads of large capacity, have the corner members thereof interconnected by reinforcing members in a manner which permits slight relative movement therebetween with the result that the desired strengthening of the bucket and proper alignment of the scoops is achieved without danger of breakage of the reinforcing members or of their connections to the corner members and without the need of excessive increases in weight. In the preferred embodiment, the reinforcement of the corner members of a bucket of the type described and the connection of this reinforcement with the corner members may be achieved in the manner illustrated in Figs. 2 to 4. As shown there.- in, reinforcing members in the form of channel or other suitably shaped structural members are interconnected to provide a substantially rigid framework adapted to extend between the two members of each pair ofA corner members as, for example, the members 14 and 15, the connection between the rigid reinforcing frame and the cor-v ner members, however, being effected by the pivotal connections, the axes of which lie in planes which extend substantially vertically, that is, generally parallel with the length of the corner bars, so that there can be a lim ited relative movement between the corners members and the rigid frame.

The nature of the presently preferred form of reinforcing framework is shown in Fig. 2 as comprising hon'- zontally extending reinforcing members 32 and 33, which are provided adjacent the tops and bottoms of the cor.- ner members, and a horizontally extending reinforcing member 34 provided intermediate the members 32 and 33. These several horizontally extending members are interconnected and further reinforced by diagonally extending reinforcing members 35 and 36 the latter being connected to the members 32 and 33 by corner plates, such as 37 and 38, while the horizontal member and the diagonal members 35 and 36 are rigidly interconnected, at the region of their intersectiomby a reinforc-y ing plate 39. The ends of the members 32, 3 3 and 34 extend to locations adjacent to, but spaced slightly from, the longitudinally extending flanges of the corner members 14 and 15 and are pivotally connected to the latter.

The pivotal connection of one end of the horizontal member 34 to the corner member or bar 14 is shown in enlarged detail in Figs. 3 and 4 as comprising spaced angle members 40 and 41 which are suitably secured as by welding, or the like, to a vertical web or ange of the member 14, the members 40 and 41 being oppositely disposed so that the legs extending outwardly from the member 14 are adjacent each other an-d are disposed substantially horizontally. These horizontally extending legs of the members 4t) and 41 receive the adjacent end of the horizontally extending member 34 in overlapping relationship with a filler plate, such as 42, preferably being secured toY the member 34 adjacent its end and adapted to rest upon the horizontal leg ofthe member 40. The reinforcing member 34, filler plate 42 and angle members 40 and 41 have aligned bores extending therethrough in which a securing means is positioned `in a manner providing for limited pivotal movement between the member 34 and the corner member 14 about an axis disposed at right angles relative to the member 34. In the construction shown, this securing means providing the pivotal connection comprises a hexagonally headed bolt 43 having a suitable nut 44 thereon which is tightened to the extent maintaining the parts in firm engagement while permitting a slight relative movement therebetween about the axis of the bolt. The nut 44 may be secured in the desired position by a suitable means such as a cotter Pin, or the. like..

The other end o f the horizontally extending member 34 is pivotally connected with the corner member or bar 15 in the same manner as has been described in detail with respect to the connection to the corner member or bar 14, and the outer portions of the horizontal members 32 and 33 are connected in similar manner to the corner members 14 and 15. Likewise, the pair of corner members or bars pivotally supported upon the shaft 13 are provided with like reinforcing members pivotally secured therein in the same manner as has just been described. It will, therefore, be apparent that the two members of each pair of corner members have a rigid reinforcing framework extending therebetween, which framework is secured to the corner members or bars of a pair thereof in a manner permitting slight relative movement about axes which lie in vertical planes. Consequently, the stresses encountered in operation of large capacity grab buckets of the type described, tending to cause relative movement of the corner members and which would result in rupture of the reinforcing members or their connections to the corner members if these were completely rigid, are relieved by slight relative movement between these members about the `aforementioned pivotal connections. Nevertheless, the corner members are sufficiently rigid and reinforced to provide for satisfactory operation of the jaws or scoops.

Figs. 5 to 8 of the drawings illustrate a modified embodimenl` of the invention which has been found advantageous with respect to large capacity grab buckets and which provides a bucket of lighter weight than those con.- structed as disclosed in Figs. 1 to 4. The bucket shown `in Fig. 5, like that in Fig. 1, comprises a hea-d block 45 having horizontally extending shafts or rods 46 and 47 supported along either side thereof on which are pivotally mounted spaced pairs of corner members or bars 48 and 4 9. The pairs of corner members or bars 48 and 4 9 have the bucket jaws or scoops 50 and 51 pivotally supported thereon in the same manner as the jaws or scoops 20 and 23, the jaws or scoops being similarly provided with hinge plates 52 and 53 pivotally connected with .the lower Sheeve block 54- Likewise, in this form of bucket the head. block 45 is provided with pulleys 55. and. the lower block. is provided with pulleys 56 for receiving the elosing rope or cable 57. Shortening and lengthening of the closing rope or cable 57 effects raising and lowering rnoverment-s,l respectively, of the lower sheave block 54 with resulting opening or closing of the jaws or scoops 50 and 51, the alignment of the jaws or scoops and equal opening and closing movement thereof being facilittaed by the Provision on.y the hinge plates 52., 53 of intermeshing teeth 58, 59 and by similar intermeshing teeth 60 provided upon horizontally extending portions of the corner members 48 and 49 adjacent their pivots 46 and 47. The bucket is suspended from, and raised and lowered by, a holding line or cable 61, as will be readily understood.

The bucket illustrated in Figs. 5 to 8 does not have horizontally extending reinforcing members adjacent the upper and lower ends of the corner members such as are provided in buckets constructed as shown in Figs. 1 to 4. A horizontally extending reinforcing member 62 is, however, provided intermediate the tops and bottoms of the two corner members or bars of each pair thereof, the ends of this member being pivotally connected to the corner members or bars in a manner similar to the member 34 in the preferred form of bucket.

As shown in Figs. 7 and 8, the corner member or bar 48 has oppositely directed angle members 63 and 64 secured thereto as by welding, or the like, so that the one leg each of these members extends adjacent each other in a substantially horizontal direction. These horizontally extending portions of the angle members 63 and 64 are, however, vertically spaced in this embodiment so that the central web 65 of the member 62 can extend therebetween, reinforcing filler members 66 and 67 being secured by welding, or the like, to this central web adjacent the ends thereof and of a thickness such as to substantially fill the space between the horizontally extending legs of the angle members 63 and 64. Aligned bores are provided through the horizontal legs of the members 63 and 64 and through the filler plates 66, 67 and the web 65 of the member 62, which aligned bores have a member extending therethrough providing a pivotal connection therebetween. In the illustrated embodiment this pivotal connection is provided by a headed pin 68, the lower end of whose shank extends beneath the horizontal portion of the angle member 64 and has a transverse bore in which may be positioned a retaining pin 69 to prevent displacement of the pivot pin 68. The other end of the member 62 is similarly pivotally connected to the second corner member or bar of the pair designated 4S .and the pair of corner members or bars 49 are, likewise,

provided with a horizontally extending reinforcing member similar to 62 and pivotally connected therewith in the manner just described.

Further reinforcement is provided between the two corner members or bars of each pair thereof by diagonally extending tension rods 70 and 71. One end of each tension rod is pivotally connected to one of the corner members of a pair thereof adjacent the upper end as by means of spaced ears or lugs 72 secured to the corner member and having suitable apertures for a pivot pin extending through the eye or clevis of the tension rod. The apertures in the ears or lugs 72 are preferably elongated slightly and the opening through the eye or clevis of the tension rod may be somewhat larger than the diameter of the pivot pin extending therethrough to provide for slight relative movement between the members. The other end of each tension rod is similarly pivotally connected to the opposite corner member or bar of a pair thereof adjacent the lower end, as will be readily apparent from Fig. 6. Preferably, the tension rods 70 and 71 are made adjustable as, for example, by forming each rod in two spaced parts with threaded adjacent ends on which are disposed a turnbuckle, such as 73, 74.

Consequently, the form of the bucket shown in Figs.

to 8, like the bucket shown in Figs. l to 4, has the two corner members or bars of each pair thereof reinforced by transversely extending members so that the desired strength and rigidity of the bucket necessary for proper operation is provided. The reinforcing members, however, are so constructed and arranged that limited relative movement may occur between the two corner members or bars of a pair thereof without breakage of any of the parts. This relative movement is made possible by the pivotal connection of the reinforcing members, such as 62, and by the fact that the tension rods 70 and 71 can be torsionally deliected in response to slight relative movement between the two corner members or bars of a pair thereof. Furthermore, the turnbuckles 73 and 74, in addition to providing for adjustment of the lengths of the tension members 70 and 71, also facilitate slight relative movement of the two corner members or bars of each pair thereof so that when such turnbuckles are provided it is not necessary to rely solely upon the torsional deflection of the bars to permit such relative movement.

Moreover, the elongated apertures in the ears or lugs 72 and/or slightly enlarged openings in the eyes or clevises of rods 70 and 71 permit slight relative movement between the rods and corner members.

lt will now be apparent that grab buckets of the clarnshell type may, in accordance with this invention, be constructed in large sizes and adapted to handle large capacity loads without the need of excessive weight and without danger of breaking of the reinforcing members, or the connections of the latter to the corner members, which reinforcing members are necessary to proper operation of such large capacity buckets. Consequently, maintenance costs and loss of productive time of the buckets are greatly reduced and the useful life of the buckets is increased. Furthermore, the provision for slight relative movement between the corner members of the buckets and the reinforcing members therebetween is effected in a manner which does not destroy the purpose of the reinforcing members, nor interfere with proper operation of the jaws or scoops of the buckets.

Although a preferred embodiment of the invention and one modification thereof have been described and illustrated in considerable detail, it is to be understood that the invention may be embodied in other forms and that changes and adaptations other than those speciiically set forth herein may be made by those skilled in the art without departing from the principles of the invention. Consequently, the invention is not to be considered as limited to the specific details of construction and arrangements of parts here illustrated and described except as may be required by the spirit and scope of the appended claims.

Having thus described the invention, I claim:

1. A grab bucket comprising a head block, a pair of elongated corner bars pivoted to said block for swinging movement about a common axis, a second pair of similar corner bars pivoted to said head block for swinging movement about a common axis parallel with and spaced from said first-mentioned axis, a pair of cooperating scoop or half bucket members, means swingingly connecting one of said scoop or half bucket members to each pair of said corner bars, means connected to said scoop or half bucket members to control movement of the latter to and from closed position, a reinforcing member extending between the two corner bars of each pair thereof, and means pivotally connecting said reinforcing members to said bars for relative movement about axes generally parallel to the length of said corner bars.

2. A grab bucket comprising a head block, a pair of elongated corner bars pivoted to said block for swinging movement about a common axis, a second pair of similar corner bars pivoted to said block for swinging movement about a common axis parallel with and spaced from said first-mentioned axis, a pair of scoop or half bucket members, means swingingly connecting one of said scoop or half bucket members to each pair of said corner bars, means connected to said scoop or half bucket members to control movement of the latter to and from closed position, a rigid reinforcing frame extending between the two corner bars of each pair thereof intermediate the said head block and the scoop or half bucket member connected to said pair of bars, and means pivotally connecting said frames adjacent the corners thereof to said corner bars for limited relative movement therebetween about axes generally parallel to the length of said corner bars.

3. A grab bucket comprising a head block, a pair of elongated corner bars pivoted to said block for swinging movement about a common axis, a second pair of similar corner bars pivoted to said block for swinging movement about a common axis parallel with and spaced from said first-mentioned axis, a pair of scoop or half bucket members, means swingingly connecting one of said scoop or half bucket members to each pair of said corner bars, means connected to said scoop or half bucket members t=control movement of the" latter toand from closedpo'- siti'eu, reinfreing' means extending between the fwocor'- ner members of each" pair thereof, the saidi reinforcing means including a pair of intersecting diagonally extend# i'ng rigidv members, and means pivotally connecting said rigid members adjacent the ends thereof to said corner bars for limited relative movement therebetween about Xes lying in substantially vertical planes.

4. A grab bucketl as defined in claim 3 and further comprising a rigid member extending horizontallyV between-the two corner bars of each pair thereof, and means pivot-ing the said horizontal member to thel corner bars between which it extends.

5'. A- grab bucket as defined in claim 3` and further comprising'. a rigid member extending horizontally be-` tween the two corner bars of eachpairthereof and rigid- ,8 1y secured' to said diagonally extending members, andmeans-'p'yoting the said horizontal member to' thev c'orne'r bars between-which it extends.

Ree'renc'es Cited in the le of this patent UNITED STATES PATENTS 

